Method of detecting impurities in molten resin
CA 2109884 C · Owner: Yasuo, Hiroyuki · Inventors: Deguchi, Hiroshige; Yasuo, Hiroyuki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of detecting impurities in a molten resin. The molten resin is passed through a passage having a window through which light can pass. Light is emitted from a light source through the window and the molten resin flowing through the passage. Sensors are used to sense a shadow produced when the light from the light source is interrupted by an impurity contained in the molten resin. Finally the size of the impurity is measured from the width of the shadow and the intensity of light of the shadow Also, judgment is made that if optical signals obtained by detecting the light that has passed through the molten resin indicate that there exist bright areas around a dark area, the dark area …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed November 24, 1993 and granted January 5, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 24, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 24, 2015.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.